The probability of an impossible event is _______.

Answer

To solve the question "The probability of an impossible event is _______.", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Probability**:
Probability is defined as the measure of the likelihood that an event will occur. It is calculated using the formula:
\[ \text{Probability (P)} = \frac{\text{Number of favorable outcomes}}{\text{Total number of outcomes}} \]

2. **Identifying an Impossible Event**:
An impossible event is an event that cannot happen. For example, rolling a 7 on a standard six-sided die is impossible.

3. **Favorable Outcomes for an Impossible Event**:
Since an impossible event cannot happen, the number of favorable outcomes for such an event is 0.

4. **Total Outcomes**:
The total number of outcomes depends on the scenario. For example, in the case of rolling a die, there are 6 possible outcomes (1, 2, 3, 4, 5, 6).

5. **Calculating the Probability**:
Using the formula for probability:
\[ P(\text{Impossible Event}) = \frac{\text{Number of favorable outcomes}}{\text{Total number of outcomes}} = \frac{0}{\text{Total outcomes}} = 0 \]

6. **Conclusion**:
Therefore, the probability of an impossible event is 0.

### Final Answer:
The probability of an impossible event is **0**.

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